Physicochemical characterization and catalytic properties of titania gel doped with lithium and rubidium

The effect on titania of doping with lithium and rubidium titania gels has been studied in samples prepared with titanium (IV) tetra-n-butoxide co-gelling with the alkaline metal precursors. Titania and doped titania were characterized by X-Ray diffraction, which showed that the catalysts were nanostructured. In samples calcined at 400°C, the crystallite size of the anatase phase was 17 and 14 nm, and 78 and 38 nm for samples calcined at 600°C, for Li/TiO ₂ and Rb/TiO ₂, respectively. The specific surface areas of doped samples (400°C) are lower in Li/TiO ₂ (90 m ²/g) than in Rb/TiO ₂(125 m ²/g). Evaluation of their basic properties has been carried out in the acetone condensation reaction. It was found that the activity strongly depended on the Li and Rb ionic radii.